Adding CSS additional class to a block
Each block that you use in the Block editor can have additional CSS classes defined using the block properties.
- Navigate to the Block editor by opening an existing page or post, or creating a new page or post as needed.
- Click on the block that you wish to modify.
- In the sidebar at right click on the label Block. If you don’t see the sidebar, click on the gear icon in order to make it appear.
- Scroll down to the Advanced section and then click on the drop-down arrow.
- Add your classes to the field labeled Additional CSS class(es).
- Click on Update or Publish once you are ready.